JPH0798471A - Camera - Google Patents

Abstract

PURPOSE:To provide a camera system capable of surely obtaining an aimed effect without requiring actions that a photographer horizontally swings a camera with hands as in the conventional manner when the photographer wants to use what is called a + or -anning' technique for emphasizing the sensation of speed at the time of photographing a moving body such as a racing car running at full speed in a car race. CONSTITUTION:A variable apex angle prism 1 is disposed between an object and a photographing lens 6, and the refractive angle of a light beam from the object is controlled so that the apex angle of the prism 1 may be kept being changed in accordance with the incident angle of reflected light from the moving body with respect to the optical axis of the lens 6 while performing exposure corresponding to the detection output of a speed sensor 3 for detecting the speed of the moving body being a main subject, and only the reflected light from the main subject reaching a photographic surface is kept in a fixed state where shake is not caused.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a still screen camera,
In particular, the present invention relates to a camera in which a variable apex angle prism is arranged in front of a photographing lens, and a light ray reflected from an object is intentionally refracted so that an image forming position of the light ray on a photographing surface can be kept constant.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a variable apex angle prism capable of changing the apex angle by enclosing a liquid having a high refractive index between two plate glasses. FIG. 5 shows a sectional view of the configuration of one example thereof. In FIG. 5, 17 is a high refractive index liquid, 18 is a plate glass, and 19 is a bellows part. Further, there has been proposed a camera anti-vibration system having an image stabilization mechanism by using this type of prism, an example of which is shown in FIG.

In FIG. 6, reference numeral 1 is a variable apex angle prism whose apex angle can be changed according to the deviation angle of the lens optical axis due to vibration. 2 is a drive actuator for changing the apex angle of the variable apex prism, 4 is a distance measurement (AF) sensor for measuring the subject distance, and 5 is photometry for measuring the exposure level of the subject. (AE) sensor, 6 is a taking lens, 7 is a lens drive actuator for performing a focusing operation of the taking lens 6, 8 is a microcomputer for controlling all operations of this camera, 9 is incident light A diaphragm mechanism 10 for limiting the shutter speed is a release switch for causing the camera to perform a photographing operation, and is generally O
It has three positions: FF, switch 1, and switch 2.

Reference numeral 11 is a shutter, and 12 is a recording medium such as a film. Reference numeral 23 is a prism apex angle sensor for constantly monitoring changes in the prism apex angle during operation of the image stabilization system, and 24 is a shake amount detection sensor that outputs a signal corresponding to the shake amount when camera shake occurs. Is.

FIG. 7 is an explanatory view of the principle of a camera anti-vibration system using the above variable apex angle prism. Reference numeral 20 is a variable apex angle prism, 21 is a photographic optical system, and 22 is a photographic surface, which will be described below.

When a light ray from an object with a subject is guided to the photographing surface 22 by the photographing lens 6, if the lens 6 moves due to camera shake, the light ray from the object also moves on the photographing surface, resulting in image blurring. Therefore, the variable apex angle prism 2
0 is arranged between the object and the photographing optical system 21, the apex angle of the prism is changed according to the deviation angle of the lens optical axis due to vibration, and the refraction angle of the light beam from the object is controlled to reach the photographing surface. The light beam can be kept in a constant state without blurring, and the effect of camera shake can be compensated.

[0007]

Here, when photographing an object, for example, a racing car running in a car race or the like, a so-called "follow shot" method is often used as a special photographing method for emphasizing the sense of speed. Used.

This is because the photographer uses his hand to shake the camera sideways in accordance with the movement of the racing car, and the image of the background or the like other than the image of the racing car, which is the main subject, is cast. It is a method of recording.

This method is a method with large uncertainty such as shaking the camera by hand, and the probability of obtaining a photograph with the composition intended by the photographer is extremely low. Therefore, in order to obtain one successful photograph, a relatively large number of films are required, which is a waste.

The present invention has been made in view of the above situation, and when performing this type of follow shot, the photographer does not need to shake the camera sideways with his / her hand, and a reliable target effect is obtained. The objective is to provide a camera system that can obtain

[0011]

Therefore, in the present invention, the speed detection means for detecting the speed of the moving body and the reflected light beam from the object are intentionally corresponded to the detection value by the speed detection means. It is intended to achieve the above-mentioned object by providing a delivery means for delivering the light to the photographic lens after refraction.

[0012]

With the configuration of the present invention as described above, an arithmetic function for performing, for example, the apex angle changing operation of the variable apex angle prism at the speed corresponding to the signal output of the speed detection sensor for detecting the speed of the main subject at the time of photographing a moving object. By intentionally refracting the reflected light beam from the object in response to the sensor output, and during the exposure time, the refraction angle of the light beam incident on the photographing lens from the main subject through the prism to the photographing lens is The above-mentioned object can be achieved by controlling the images to be formed at the same position on the photographing surface.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. (Structure) FIG. 1 is a structural block diagram of an embodiment of a camera system according to the present invention, which is the same as that shown in FIG. (Corresponding) components are represented by the same reference numerals. Reference numeral 1 denotes a variable apex angle prism, 2 a drive actuator for changing the apex angle of the variable apex angle prism 1, 3 a moving body speed sensor for detecting the speed of a moving body as a main subject, 4
Is a range finding (AF) sensor for measuring the subject distance,
5 is a metering for measuring the exposure level of the subject (A
E) sensor, 6 is a taking lens, 7 is a lens drive actuator for performing a focusing operation of the taking lens 6, and 8 is
It is a microcomputer for controlling all the operations of this camera.

Reference numeral 9 is a diaphragm mechanism for limiting incident light, and 10 is a release switch for causing the camera to perform a photographing operation, which is generally provided with three positions of OFF, switch 1 and switch 2. There is. Further, 11 is a shutter, 12 is a recording medium such as a film, and 13 is a recording medium.
It is a mode selector for setting a shooting mode.

(Principle) FIG. 2 shows the variable apex angle prism 1 described above.
FIG. 9 is a principle explanatory view of the camera system of the present embodiment using, where 14 is a variable apex angle prism, 15 is a photographing optical system, and 16 is
Is a shooting surface, and the operation will be described below with reference to this drawing;
When the object moves when being guided to 6, the light rays from the object also move on the shooting surface, causing image blurring.

Therefore, the variable apex angle prism 14 is arranged between the object and the photographing optical system 15, and the apex angle of the prism 14 is set to the incident angle of the reflected light of the moving body with respect to the lens optical axis during the exposure time. Keep changing accordingly. In this way, by controlling the refraction angle of the light ray from the object and keeping only the reflected light from the moving body that reaches the shooting surface 16 in a constant state without blurring, only the background is blurred. Therefore, the image has the same effect as the panning shot.

(Operation) Next, details of performing the above-mentioned operation in the camera according to the system of the present embodiment will be described with reference to FIGS. 1 and 2 and FIG. 3 of the photographing operation sequence flowchart; In S1, when the first stroke of the release switch 10 is pressed (SW1), the AF sensor 4 and the AE sensor 5 are activated in step S2 and thereafter, and distance measurement and photometry are started. After this, step S3
If the mode selector 13 is not in the panning mode,
After the distance measurement in step S7, it is detected in step S8 that the second stroke of the release switch 10 is pressed (SW2), AF and AE locks are performed in step S9, and then the shutter 11 is pressed in steps S15 and S16. To activate the exposure and end the shooting.

On the other hand, if the mode selector 13 is in the follow shot mode in step S3, AF lock is performed after performing the same operation as in the normal mode with the first stroke (SW1) of the release switch 10 in step S1. In step S4, the moving body speed sensor 3 is operated to detect the speed.

As a method for detecting the speed, for example, a method has been proposed in which the reflected light of an object is formed on a CCD (solid-state image pickup device), and the speed vectors are extracted by comparing continuously incident images. Therefore, detailed description thereof will be omitted in the description of the operation of the present embodiment. Further, in the present embodiment, focusing in the follow shot mode is
Description will be made on the premise that the so-called “placement pin” is set before shooting.

When the speed detection by the speed sensor 3 is completed in step S4, the detected speed is used to perform a calculation for setting the variation amount of the prism apex angle per unit time in the variable apex angle prism 14. When performing this calculation, it is assumed that the speed v (m / s) of the moving body detected earlier, the object distance L (m), and the exposure time at the set shutter speed are T (s). Here, this calculation method will be described with reference to FIG.

From opening to closing of the shutter 11, that is,
Letting ΔL (m) be the moving distance of the racing car (moving body) in the figure as an object during the exposure time T (s), ΔL = v · T.

The prism apex angle displacement angle is θ _{out (rad)} , and the displacement angle of the incident light from the moving body after passing the prism with respect to the optical axis is θ
_{x (rad)} , where n is the refractive index of the liquid inside the prism, then θ ₁ / θ ^· ₁ = n ... Equation Here, if n is set so that θ ^· ₁ = θ _out , θ _x = ( n-1) _.theta.out ... Further, from FIG. 4, it is expressed as θ _out = (n−1) ⁻¹ · tan ⁻¹ (ΔL / L).

During the exposure time T (s), the prism apex angle variation amount Δθ _{v (rad / s)} per unit time within the exposure time for forming an image of the incident light from the moving body at the same position on the photographing surface. ₎ Becomes Δθ _v = θ _out / T = (n−1) ⁻¹ · tan ⁻¹ (ΔL / L) · T ⁻¹ . The prism drive actuator 2 is controlled so that the prism 1 (14) is displaced by this Δθ _v . In other words, during the exposure time, by controlling the apex angle of the prism 1 to change by Δθ _{v (rad / s)} , the reflected light from the moving body entering the taking lens 6 can be reflected at the same position on the taking surface. To form a panning image.

After the above calculation is completed, it is necessary to accelerate the prism 1 in the opposite direction to the movement of the prism 1.
The prism 1 is set in advance with the position returned from the optical axis by the prism vertical angle change amount α _(rad) as the initial position. After the above operation is completed, the release switch 10 is pressed in step S8.
If the second stroke (SW2) of the prism 1 is pressed, the AE lock is performed in step S9, the prism drive actuator 2 is moved, and after the run-up of the prism 1 is completed, the shutter 11
, And exposure is performed.

[0025]

As described above, according to the present invention,
When shooting moving objects, the function to change the apex angle of the variable apex angle prism at the speed corresponding to the signal output of the moving body speed sensor that detects the speed of the main subject allows the main subject to be exposed during the exposure time. Since the angle of refraction of the light beam incident on the shooting lens through the prism can be controlled so that only the main subject forms an image at the same location on the shooting surface, the conventional method can be used while adjusting to the movement of a racing car, for example. Thus, it becomes possible to reliably record and record an image such as a background other than the image of the main subject without the photographer having to use the hand to shake the camera sideways.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an embodiment of a camera system.

FIG. 2 is an explanatory view of the principle of the system shown in FIG.

FIG. 3 is an imaging sequence flowchart of the system shown in FIG.

FIG. 4 is an explanatory diagram of a calculation method of the system shown in FIG.

FIG. 5 is a diagram showing a configuration example of a conventional variable apex angle prism.

FIG. 6 is a configuration block diagram of an example of a conventional camera image stabilization system.

FIG. 7 is an explanatory view of the principle of the system shown in FIG. 1,14,20 Variable apex angle prism 2 Prism drive actuator 3 Moving body speed sensor 4 AF sensor 5 AE sensor 6,15,21 Shooting lens 9 Aperture 10 Release switch 11 Shutter 13 Mode selector 16,22 Shooting surface 17 High refractive index liquid

Claims (1)

[Claims] 1. A velocity detecting means for detecting the velocity of a moving body, and a light ray reflected from an object, which is intentionally refracted in accordance with a value detected by the velocity detecting means, and then sent to a photographing lens. A camera having a sending means.